condition mean min max ZT0-3 5.3384275 5.15454 5.522315 ZT4-7 3.3445549999999997 3.3445549999999997 3.3445549999999997 ZT8-11 4.01001 4.01001 4.01001 ZT12-15 0 0 0 ZT16-19 5.662050000000001 5.662050000000001 5.662050000000001 ZT20-23 5.69745 5.69745 5.69745